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Jsr03 9v Problem

Started by Branko, July 07, 2011, 09:26:45 PM

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Branko

Hi,

i build a jsr03 9V as stated on BOM with two red LED. I double checked the parts. if I connect to power (without load) the two LED light up for about 2 secondes then stop light. the V in is about 18,5 V and the V out is 16,1 V (with tin bolbs on the sense pads) i use an lm317, ad825, bd 139 and tl431. R10 is jumper, r13 10K. what to check where to measure?

thx

Branko

peranders

R12 not mounted? Only R11?

Start to measure around the opamp, pin 2, 3 , 6 and 7

The values should be

Pin 3 Approx. 9.50 V
Pin 2 the same as pin 3 +- 2 mV
Pin 6 7-9 V
Pin 7 19 V
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

peranders

#2
You have:
Vin 18,3 V (no load) IC3 (AD825) pin 2: 0; 3: 8,72V; 6: 14,98V; 6: 15,6 V

8.72 V is good
Pin 2, R8, R9 are both 1k? R10 jumper or resistor?

Have you connected the sense inputs? Put a tin blob on the J1 and J2 on the solderside.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Branko

#3
Hi,

R10 jumper. Tin blobs are in place. R8/R9 1K.
Moved R11 (47R) to R12. R11 open

Branko

peranders

Can you measure across R8 and R9?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Branko

#5
R9 0V; R8 0V

Branko

peranders

Check R8 and it's connection to the output. R3 is connected to R8 and the LM431 seems to be working.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Branko

Hi,

I will check after noon when I am back home. I use a TL431 not a LM431. Is that a problem?

thx

Branko

peranders

Should work and you have also nearly 8.5 volts which is correct for 19 V out. Check carefully that all parts are their right positions.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Branko

Hi,

double check sometimes is not enough :oops:! As I tried to move R11 to R12 I moved R8 to R11.

After correcting these things here are the Values:
Vin 18,5V (LEDs shows light for a moment, then goes dark) Vout 16,5 V

IC4: Pin 2 -- 8,06 V Pin 3 -- 8,52 V Pin 6 -- 15,6V  Pin 7 -- 16,53V

R3 -- 7,33 V  R7 -- 0,0 V  R8 -- 8,05 V R9 -- 8,05 V R10 -- Jumper(would 470R be better option?); R11 47R in Place; R12 open.
IC2 TL431 not LM431

Branko

peranders

9 volts out, you should have 4.5 volts and the reference. Could you repeat the resistor values around the TL431?

I was into 19 volts out which somebody wanted.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Branko

Hi,

the values around TL431 are:

R4-   10K-    6,27 V
R5-   3K9-    2,44V
R16- 220R-  0V
R3-  3K3-     7,02V
R7-  470R-   0 V
R8-  1K-      7,92V
R9-  1K-      7,92V.      The Ohm values are from the color Code not measured in place.

I tried to measure the Ohm-Value of R4 with Vin connected. When i put the probe to the legs of R4 the LED begin to light?

Branko

Branko

Hi,

I have build a second board with the equal parts (as listed in the .xls File from download for 9V. Only difference TL431. R10 Jumper. Two red LED). I get the same behavior: LED light up for ca. 1 second and go dark. If I measure resistance over R4 with Ohmmeter LED start light again. Minimal different measurement of values. A version for 5 V i build too works well: Vout 4,92 V(not tested with load yet). Basically the same parts only other resistor values (as per .xls file for 5V)

Branko

peranders

It seems that I have mixed up with the 19 V version. I'm on a bus right so give me two hours and I can calculate the right values.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

peranders

Have you selected the 9 V sheet in the excel file? I have different voltages in the same file.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff